This project was designed to conduct comparative studies of the role of delayed hypersensitivity, humoral immunity and interferon in neurotropic infections as well as in perinatal infections. The development of immunologic methodology for evaluating intra-uterine and central nervous system (CNS) diseases is the principal goal proposed. For this purpose serologic survey with spinal fluid and sera from patients with chronic diseases of the CNS will be conducted in parallel with matched controls. Since a constant residual amount of specific IgM seems to be associated with persistent viral infections particular emphasis will be placed upon isolation and purification of 19S immunoglobulins followed by determination of its antibody specificity. The study of the development of the fetal immune system will be conducted in Rhesus monkeys and this evaluation will be correlated with fetal susceptibility to infectious agents.